Collsions未被檢測到，儘管它已按照http://www.raywenderlich.com上的規定實施

Question

儘管代碼指定應將球從視圖中移除並且應打印「點擊」，但不會發生任何反應。

import SpriteKit 

class GameScene: SKScene, SKPhysicsContactDelegate { 
    struct PhysicsCatagory { 

     static let none : UInt32 = 0 
     static let all : UInt32 = UInt32.max 
     static let ball :UInt32 = 0b1 
     static let basket : UInt32 = 0b10 

    } 
    var basket = SKSpriteNode() 

    //moves towards top right corner of the screen 
    let actionMoveUpRight = SKAction.moveByX(60, y: 60, duration: 0.2) 
    //moves towards bottom center 
    let actionMoveDownLeft = SKAction.moveByX(-60, y: -60, duration: 0.2) 
    //moves towards top left corner of the screen 
    let actionMoveUpLeft = SKAction.moveByX(-60, y: 60, duration: 0.2) 
    //moves towards bottom center 
    let actionMoveDownRight = SKAction.moveByX(60, y: -60, duration: 0.2) 
    // moves down 
    let actionMoveDown = SKAction.moveByX(0, y: -50, duration: 0.2) 
    let basketCategoryMask: UInt32 = 0x1 << 1 
    let ballCategoryMask: UInt32 = 0x1 << 2 

    override func didMoveToView(view: SKView) { 
     /* Setup your scene here */ 
     // setting background colour to green 
     self.backgroundColor = SKColor.greenColor() 
     // creating a sprite node named basket and asigning it to an image of a 2D drawn basket 
     basket = SKSpriteNode(imageNamed: "basket") 
     //intiallizing basket's location and size 
     basket.position = CGPointMake(self.size.width/2, self.size.height/8) 
     basket.size.height = 50 
     basket.size.width = 75 
     basket.physicsBody = SKPhysicsBody(rectangleOfSize: basket.size) 
     basket.physicsBody?.dynamic = false 
     basket.physicsBody?.categoryBitMask = PhysicsCatagory.basket 
     basket.physicsBody?.categoryBitMask = PhysicsCatagory.none 
     basket.physicsBody?.usesPreciseCollisionDetection = true 
     self.addChild(basket) 
     //adding the basket to the scene 

     physicsWorld.contactDelegate = self 
     //creating the action that adds the balls to the scene 
     let updateAction = SKAction.runBlock { 


      var leftOrRight = arc4random_uniform(2) 
      if leftOrRight == 0 { 
       self.physicsWorld.gravity = CGVectorMake(-0.5,-2) 
      } 
      if leftOrRight == 1 { 
       self.physicsWorld.gravity = CGVectorMake(0.5, -2) 
      } 
      var ball = SKSpriteNode(imageNamed: "redBall") 
      ball.position = CGPointMake(self.size.width/2, self.size.height) 
      ball.setScale(0.5) 
      ball.size.height = 20 
      ball.size.width = 35 
      ball.physicsBody = SKPhysicsBody(circleOfRadius: ball.size.height/2) 
      ball.physicsBody!.dynamic = true 
      self.addChild(ball) 
      ball.physicsBody? = SKPhysicsBody(circleOfRadius: ball.size.width/2) 
      ball.physicsBody?.dynamic = true 
      ball.physicsBody?.categoryBitMask = PhysicsCatagory.ball 
      ball.physicsBody?.contactTestBitMask = PhysicsCatagory.basket 
      ball.physicsBody?.collisionBitMask = PhysicsCatagory.none 


     } 

     let waitDuration : NSTimeInterval = 2.0 
     let updateAndWaitAction = SKAction.sequence([updateAction,SKAction.waitForDuration(waitDuration)]) 
     let repeatForeverAction = SKAction.repeatActionForever(updateAndWaitAction) 
     self.runAction(repeatForeverAction) 
    } 

    override func touchesBegan(touches: NSSet, withEvent event: UIEvent) { 
     /* Called when a touch begins */ 

     for touch: AnyObject in touches { 
      let location = touch.locationInNode(self) 
      if basket.position.y < 125 { 
       if location.x > basket.position.x { 

        if location.y > basket.position.y { 
         basket.runAction(actionMoveUpRight) 
        } 

        else { 
         basket.runAction(actionMoveDownRight) 
        } 

       } 

       else if location.x < basket.position.x { 

        if location.y > basket.position.y { 
         basket.runAction(actionMoveUpLeft) 
        } 
        else { 
         basket.runAction(actionMoveDownLeft) 
        } 
       } 

      } 
      else { 
       basket.runAction(actionMoveDownLeft) 
      } 
     } 

    } 

    func didBeginContact(contact: SKPhysicsContact){ 

     var firstBody : SKPhysicsBody 
     var secondBody : SKPhysicsBody 



     if contact.bodyA.categoryBitMask < contact.bodyB.categoryBitMask { 

      firstBody = contact.bodyA 
      secondBody = contact.bodyB 

     } 

     else { 

      firstBody = contact.bodyB 
      secondBody = contact.bodyA 

     } 

     if ((firstBody.categoryBitMask & PhysicsCatagory.ball != 0) && (secondBody.categoryBitMask & PhysicsCatagory.basket != 0)) { 
      var y = true||false 
      collisionDidHappen(firstBody.node as SKSpriteNode, basket: secondBody.node as SKSpriteNode) 

     } 

    } 

    func collisionDidHappen (ball : SKSpriteNode, basket : SKSpriteNode) { 

     println("Hit") 
     ball.removeFromParent() 

     println("collsion did happen") 
    } 
} 

Answer 1

刪除碰撞位掩碼線。